Hippocampal SWRs represent another prominent network state associated with hippocampal-cortical interactions. SWRs are high-frequency (150–250 Hz) transient oscillations (~100 ms) seen prominently during slow-wave sleep, and in the awake state during consummatory behaviors and periods of low movement speed [7,13,19]. These highly synchronized events are associated with fast time-scale replay of place cell sequences representing trajectory events [7,42–46]. Hippocampal reactivation during sleep has long been proposed to be a part of a neocortical dialogue for consolidation of memory related information [47]. Indeed, interactions with cortical regions, specifically enhanced activity correlations and coordination of LFP patterns, have been observed during sleep SWRs [48–52]. In contrast, the role of awake SWRs has only begun to be elucidated recently (differences between awake and sleep SWRs are also reviewed elsewhere [53]), with evidence suggesting a role of awake SWRs in memory consolidation, memory retrieval to guide future actions, as well as planning [7,46,54,55]. Hippocampal replay during awake SWRs comprises reactivation of place cell sequences in forward and reverse temporal order, as well as novel shortcut sequences, suggestive of a diverse role in reinforcement learning,
